Method of manufacturing stab-resistant fabric using water punching

ABSTRACT

A method of manufacturing stab-resistant fabric using water punching is provided. Aramid fabric and nonwoven aramid fabric are combined through water punching, thereby enhancing activities by ensuring flexibility and stab-resistance performance, and the method is an aramid composite fabric manufacturing method which performs water punching with pressure of 50 to 250 bar when the water punching is performed.

FIELD OF THE INVENTION

The present invention relates to stab-resistant fabric, and moreparticularly, to a method of manufacturing stab-resistant fabric usingwater punching.

BACKGROUND OF THE INVENTION

In developing a stab-resistant vest (including stab-proof clothing,stab-proof gloves, or the like) or stab-resistant fabric for effectivelyprotecting bodies or the like from impact of a sharp object such as aknife or awl, existing stab-resistant vest (stab-resistant fabric) isheavy in weight and stiff in texture, which are not desirable foractivities.

This is because when a stab-resistant vest is manufactured, a multilayerstab-resistant material is stacked such that a knife or an awl cannotpenetrate therethrough, and a thin metal plate or high-strength plasticand fabric coated with inorganic particles, and the like are used. Sucha stab-resistant vest is inevitably heavy and stiff, causing a wearer toslow in movement.

Thus, as a method for improving such a stab-resistant vest (orstab-resistant clothing), a demand for developing stab-resistant fabric,having the greatest importance in stab-resistant vest, to develop aproduct which is light in overall weight and supports excellent activityhas grown.

In order to manufacture a stab-resistant vest supporting excellentactivity, Korean Patent No. 1385003 (entitled Stab-resistant fabric withinorganic particles attached thereto and manufacturing method thereof)of the present applicant proposes a method of increasing flexibility offabric by attaching inorganic particles such as alumina, titaniumdioxide, or silicon carbide to aramid fiber formed of yarn with hightenacity or treating a manufactured stab-resistance fabric with asoftening agent.

The stab-resistant fabric manufactured by the above method is reduced inweight and has increased flexibility, compared with an existingstab-resistant fabric, but disadvantageously has a short endurance termin that the inorganic particles attached to the surface of the fabricmay be separated.

Thus, it is required to develop fabric itself having excellentstab-resistance performance.

SUMMARY OF THE INVENTION

Therefore, the present invention has been made in view of the aboveproblems of the prior arts, and it is a primary object of the presentinvention to provide stab-resistant fabric which is light in overallweight compared with an existing stab-resistant vest by enhancingstab-resistance performance of fabric itself.

Another object of the present invention is to provide stab-resistantfabric supporting excellent activity through lightness.

According to one aspect of the present invention, there is provided amethod of manufacturing stab-resistant fabric using water punching,including: interlacing an aramid nonwoven fabric in a high strengthfabric formed of aramid yarn through water punching.

The present inventors recognized that the stab-resistance performancecan be increased by enhancing the density of stab-resistant fabric byinterlacing a micro-aramid fiber (aggregate) constituting an aramidnonwoven fabric in a high strength fabric formed of aramid yarn througha water punching process using high pressure water, and devised thepresent invention.

High Strength Aramid Fabric

High strength fabric as biaxial fiber aggregate is formed using highstrength aramid nonwoven fabric or filament yarn as uniaxial fiberaggregate. Fiber is preferably fabric, and twilled fabric or plainfabric is illustrated. In order to achieve a stab-resistance function,the density of fiber should be high, and knitted work has relatively lowdensity compared with fabric, and thus, plain fabric or twilled fabricis selected.

Further, in the present invention, the aramid yarn is preferably spunyarn 40/3 (tex 40/strands 3) to 60/2 or 500 to 600 denier filament yarn,and this is for appropriate fabric density and integration of yarn infabric.

Also, in the present invention, the density of the fiber is 30×30 ply(wrap threads×weft threads) to 85×85 ply (wrap threads×weft threads)/5cm, a basic weight is 100 to 200 gsm, and air permeability is 5cm³/cm²/s or greater. When the density is less than 30×30 ply/5cm,stab-resistance performance is weak, and when the density exceeds 85×85ply/cm, there is a difficulty in weaving fabric. It is preferable tohave 60/2, 85×75 ply/5 cm, and 140 gsm. Also, if the air permeability ofthe fabric is less than 5 cm³/cm²/s, a suction function within a rolleris impossible to perform, making interlacing between aramid fabric andnonwoven fabric defective or making it impossible to interlace aramidfiber and nonwoven fabric.

Aramid Nonwoven Fabric

Nonwoven fabric manufactured by entwisting aramid web using spunlacethrough a non-adhesive water jet stream or collecting aramid web in aconveyer belt and then needle-punching it is appropriate. The nonwovenfabric formed of aramid fiber having fineness of 3 to 6 denier, andhaving a basic weight of 40 to 70 gsm and air permeability of 100cm³/cm²/s or greater is illustrated. The range of the above numericalvalues is selected in consideration of penetration of nonwoven fiberinto aramid fiber.

Water Punching Process

The present invention features that, in a state where aramid nonwovenfabric is positioned on aramid fabric, a high pressure fluid is jettedfrom the nonwoven fabric toward the aramid fabric to allow the nonwovenfabric to be interlaced to be combined between the fiber of the aramidfabric. Here, the combining of the aramid fabric and the nonwoven fabricis performed through water punching without using a separate adhesive,and the aramid fabric and the nonwoven fabric are combined to formintegrated fabric.

Water punching is a method of allowing fiber to continuously pass withhigh pressure water to increase the density of fiber and a combiningforce between fibers, and as the strength (water pressure) of waterpunching is increased, the rigidity of aramid fabric is increased andthe interlacing between nonwoven fabric and fiber is increased.

In the present invention, the water pressure of water punching may be 50to 250 bar. When water punching is continuously performed with waterpressure of 50 to 250 bar, a water punching pattern may appear on asurface of the fabric. Such stripe pattern may be removed through randomvibration. If the pressure is less than 50 bar, inter-fiber combining isnot normally made to degrade strength and the fibers may be easilyseparated, and if the pressure is greater than 250 bar, good performancemay be obtained but elongation is lowered to reduce flexibility. At aninitial stage, the fabric may be water-punched with low water pressureto restrain damage to the fabric, and the fabric may be water-punchedwith high water pressure during a main water punching process to allowthe fibers to be effectively interlaced and allow a portion of aramidnonwoven fabric to push into the surface of the aramid fabric so as tobe combined in a wedge form, thus manufacturing stab-resistant fabrichaving strong combining force.

In case of a multistage water punching process greater than one stage,how strong water pressure is to be applied by stages may be determinedby a person skilled in the art as necessary.

In the present invention, water punching may move the fabric at a speedof 3 m/min or higher, preferably, at a speed of 3 to 10 m/min. If themoving speed of the fabric is too high, interlacing may be defective,and if the moving speed thereof is too low, mass-production of thefabric manufacturing process is degraded.

When the composite aramid fabric manufactured in the present inventionis not properly dried, stab-resistance performance may be degraded, andthus, it is preferred that the fabric undergoes a dry process at atemperature of about 240° C. for 60 seconds after the water punchingprocess.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present invention willbecome apparent from the following description of embodiments, given inconjunction with the accompanying drawings, in which:

FIG. 1 is a surface-enlarged photograph of general aramid fabric.

FIG. 2 is a surface-enlarged photograph of general aramid nonwovenfabric.

FIG. 3 is a conceptual view of a water punching apparatus formanufacturing composite aramid fabric according to an embodiment of thepresent invention;

DETAILED DESCRIPTION OF THE EMBODIMENT

Hereinafter, an embodiment of the present invention will be described.

Embodiment 1

Aramid fabric (plain fabric) having 60/2, 85×75 ply/5 cm and basicweight of 140 gsm using Kevlar of DuPont as yarn and Heracron nonwovenfabric (40 gsm) of Kolon as reinforced fabric were prepared. In FIG. 3,preliminary interlacing was performed with pressure of 70 bar by nozzle#1 of a water punching device. Secondary interlacing was performedrespectively with pressure of 100 bar by nozzle #2 and with pressure of110 bar by nozzle #3 through a subsequent continuous process. Maininterlacing was performed with pressure of 250 bar by nozzle #4.

In addition, stripe patterns formed at predetermined intervals wereremoved with pressure of 100 bar and through random vibration by nozzle#5. The interlaced aramid fabric was dried at a dry temperature of 240°C. for 60 seconds and wound to obtain stab-resistant fabric having abasic weight of 180 g/m².

Comparative Example 1

Aramid fabric (plain fabric) having 60/2, 85×75 ply/5 cm and a basicweight of 140 gsm using Kevlar of DuPont as yarn was prepared.

Stab-resistance performances of the fabric of Embodiment 1 of thepresent invention and the fabric of Comparative Example 1 prepared abovewere tested based on NIJ Standard 0115.00 (E1).

TABLE 1 Total Basic Stab-resistance weight (g/m²) weight (g/m²)performance (mm) Embodiment 1 3600 180 2 Comparative 3780 140 5 Example1

The comparison between Embodiment 1 and Comparative Example 1 shows thatthe stab-resistance performance of the composite aramid fabric usingwater punching according to the present invention is superior, althoughit is light in weight, compared with otherwise fabric.

According to the present invention described above, stab-resistantfabric capable of effectively protecting it from impact of a sharpobject such as a knife or awl is provided. Further, the presentinvention can also be used in manufacturing a stab-resistant vest or thelike supporting excellent activity through lightness.

While the invention has been shown and described with respect to theembodiments, the present invention is not limited thereto. It will beunderstood by those skilled in the art that various changes andmodifications may be made without departing from the scope of theinvention as defined in the following claims.

What is claimed is:
 1. A method of manufacturing stab-resistant fabricusing water punching, comprising: interlacing an aramid nonwoven fabricin a high strength fabric formed of aramid yarn through water punching.2. The method of claim 1, wherein a tissue of the high strength fabricis a tissue selected from plain fabric and twilled fabric.
 3. The methodof claim 1, wherein the aramid yarn is spun yarn 40/3 (tex 40/strands 3)to 60/2 or 500 to 600 denier filament yarn.
 4. The method of claim 1,wherein the density of the fabric is 30×30 ply (wrap threads×weftthreads) to 85×85 ply (wrap threads×weft threads)/5 cm, a basic weightis 100 to 200 gsm, and air permeability is 5 cm³/cm²/s or greater. 5.The method of any one of claim 1, wherein the nonwoven fabric is formedof aramid fiber having fineness of 3 to 6 denier, and has a basic weightof 40 to 70 gsm and air permeability of 100 cm³/cm²/s or greater.
 6. Themethod of any one of claim 2, wherein the nonwoven fabric is formed ofaramid fiber having fineness of 3 to 6 denier, and has a basic weight of40 to 70 gsm and air permeability of 100 cm³/cm²/s or greater.
 7. Themethod of any one of claim 3, wherein the nonwoven fabric is formed ofaramid fiber having fineness of 3 to 6 denier, and has a basic weight of40 to 70 gsm and air permeability of 100 cm³/cm²/s or greater.
 8. Themethod of any one of claim 4, wherein the nonwoven fabric is formed ofaramid fiber having fineness of 3 to 6 denier, and has a basic weight of40 to 70 gsm and air permeability of 100 cm³/cm²/s or greater.
 9. Themethod of any one of claim 1, wherein the water punching is performedwith water pressure of 50 to 250 bar.
 10. The method of any one of claim2, wherein the water punching is performed with water pressure of 50 to250 bar.
 11. The method of any one of claim 3, wherein the waterpunching is performed with water pressure of 50 to 250 bar.
 12. Themethod of any one of claim 4, wherein the water punching is performedwith water pressure of 50 to 250 bar.